Case role

Case roles, according to the work by Charles J. Fillmore, are the semantic roles of noun phrases in relation to the syntactic structures that contain these noun phrases. The term case role is most widely used for purely semantic relations, including theta roles and thematic roles, that can be independent of the morpho-syntax. The concept of case roles is related to the larger notion of Case, which is defined as a system of marking dependent nouns for the type of semantic or syntactic relationship they bear to their heads. Case traditionally refers to inflectional marking.
The relationships between nouns and their containing structures are of both syntactic and semantic value. The syntactic positional relationships between forms in sentences vary cross-linguistically and allows grammarians to observe semantic values in these nouns by examining their syntactic values. Using these semantic values gives the base for considering case roles in a specific language.
In addition to its inventory of structural cases, case theory includes a series of lexical cases that are assigned at deep structure in conjunction with theta role assignment. In addition to its relation to Case, these semantic notions of case role are also closely related to morphological case.

Inventory of case roles

The following list of case roles is frequently distinguished in literature but is not an exhaustive list, as there is no consensus on the universal inventory of roles, nor a universal agreement as to the correct assignment of constituents to roles.

Case Role	Description	Example
Patient	Fillmore refers to this case role as 'object' or 'objective' and can be described in three ways: an entity viewed as existing in a state or undergoing change an entity viewed as located or moving an entity viewed as affected by an entity	1. The sky is blue. 2. The lion is in the cave. 3. The bird ate the worm.
Agent	An entity that performs an activity or brings about a change of state	The robots assembled the car.
Instrument	The means by which an activity or change of state is carried out	She squashed the spider with a slipper.
Experiencer	The creature experiencing an emotion or perception	They love music.
Location	The position of an entity, referring to both the temporal and spatial roles	The vase is on the table. or Canada Day is on a Tuesday.
Source	The point from which an entity moves or derives	They got news from home.
Destination	The point to or towards which an entity moves or is oriented	He turned to the altar and walked towards it.
Recipient	A sentient destination	She gave her spare change to the collectors.
Purpose	The purpose of an activity	He went to the Red Rooster for some take-out.
Beneficiary	The animate entity on whose behalf an activity is carried out	She did the shopping for her mother.
Manner	The way in which an activity is done or the way in which a change of state takes place	He did it with great skill.
Extent	The distance, area or time over which an activity is carried out or over which a state holds	It lasted the winter.
Possessor	The entity that possesses another entity	I saw John's golf clubs.

Early contributions to case role

Roman Jakobson's work on case roles in Russian

In his article on the case system of Russian, Roman Jakobson closely examines case assignment and argues for a feature decomposition of case on the basis of semantic considerations. Jakobson proposed a three-feature binary case system for Russian case which includes the following: ±marginal, ±quantifying, and ±ascriptive, where the negative value is considered to be unmarked. The term marginal distinguishes the direct and non-direct cases; only the -marginal cases may occur in subject and object position. Quantifying indicates the relevance of the extent to which the noun is a participant in the event. Ascriptive puts emphasis on directionality.
Jakobson considers cases to be bundles of these three features, which can be assigned to morphological cases:

Case

Marginal

Quantifying

Ascriptive

Nominative

He uses these decomposed case features to account for the case alternations in subject and object position, and argues for how there should be a universal inventory of case roles.

Multiple case roles

There is a theory that multiple case roles can be assigned to noun phrases. The reasons for having more than one case role is due to the differences in the sentences’ semantic effects. Bhat proposed that the speaker of a language would have the option of assigning any single case role out of the multiple case role alternations available in a given context. This is not done by a transformational rule, but due to the deep structure representations.
Examples
|| John sprayed the wall with paint.
|| John sprayed paint on the wall.
In comparing sentences and, it demonstrates that the surface structure representation for each sentence is different. However, in order to account for the meaning distinctions that exist in and, it has been demonstrated that these distinctions are due to the differences in the deep structures of each sentence and can be resolved by assigning a different case role to the NP. With 'paint' acting as an instrument, and 'the wall' being the location, sentence might infer that all the paint was used, but that not necessarily all the wall was covered. Sentence might imply that the whole wall is covered, but that John did not use all the paint he had available to him.

Fillmore's alternative theory

Conversely, Fillmore suggested that in the case of sentences following the structure of the above examples, the noun phrases are not assigned multiple case roles, but instead retain the same case roles in both sentences. The difference in meaning is attributed to a transformation that takes both identical deep structures and chooses the direct object as it appears in the surface form.

Examples in Kannada

affords some good evidence of how multiple case roles can be assigned to NPs in the following two examples: how NPs can be assigned either Object or Location case roles, and how NPs can be assigned either Agent or Experiencer case roles.
Evidence for multiple case roles demonstrated in Kannada: NPs can be assigned either object or location case roles. Evidence is found from the meaning distinctions of exhaustiveness:
implies that the cat climbed the tree from the ground itself, whereas has no such implication. The common feature of these two uses is that whenever an element occurs as the object case role, it gets the added meaning of being exhaustively affected by the action denoted by the verb as seen in . No such additional meaning is observed in sentences in which the element has been used as a Location case role.
How NPs can be assigned either agent or experiencer case roles: Evidence found from the meaning distinctions of volition.
Although both sentences indicate the same event, the meaning difference is due to the fact that in Raju, as the agent, is considered to have acted volitionally, and is hence held responsible for that event, whereas in he, being an experiencer, is involved in that event only non-volitionally, and hence one does not hold him responsible for it.

Relating case roles to morphological case and structural Case

Semantic vs. morphological

The semantic category of case is related to morphological case. Morphological case reflects the ranking of arguments, while semantic case encodes a semantic relation between the DP and the governing head. Morphological case is typical of complements and is licensed by structural Case. By contrast, semantic case is typical of adjuncts; it is only licensed by the meaning of the head. From the case roles proposed by Fillmore, it was demonstrated that case roles appeared where the morphological cases of dative, genitive or instrumental appeared:

The experiencer case role
The recipient case role
The possessor case role
The partitive case role
The instrument case role

The following are observations from Sigurðsson on the "case-semantics" in case-languages demonstrating how morphological case is not blind to semantics:

Agentive subjects are nominative
Indirect objects are either dative or accusative
Most benefactive objects are dative
Most malefactive objects are accusative
Instrumental DP-objects are dative
If a lexical item has a choice between an accusative or a dative complement, then that choice is normally semantically controlled
Morphological vs. structural

is related to structural Case in the following ways:
Structural Case is a condition for arguments that originates from a relational head, while morphological case is a property that depends on the NP or DP complement. The relationship between morphological case and structural case is evident in how morphological case is subject to case agreement whereby the morphological case appearing on a DP must be licensed by the syntactic context of the DP.
In much of the transformational grammar literature, morphological cases are viewed as determined by the syntactic configuration. The accusative case is assigned through a structural relation between the verbal head and its complement. For example, the direct complement of a verb is assigned accusative, irrespective of any other properties that it might have. It must be acknowledged that it is not the accusative alone that is structural, rather the specifier of a NP is in the genitive in many languages, and so is the direct object of a nominalized verb.